JPS63243808A - In-tube inspecting instrument - Google Patents

Abstract

PURPOSE:To obtain a highly reliable device which can specify a circumferential detection position by providing a detection head internally with its rotation detecting means. CONSTITUTION:The rotation detection part 9 fixed in the detection head 51 detects the quantity of rotation of the head 51. Here, a disk 10 is held by supports 15a and 15b, etc., and rotate freely, and a weight 11 is fitted and faces in the gravitational direction at all times, thereby stabilizing the disk. The supports 15a and 15b are fixed to the head 51 and rotates as the head rotates, so that the position relation with the disk 10 varies. The variation can be detected by reading optical marks (d and e) of plural tracks 12a-12c of the disk 10 by light projectors 16a-16c and photodetectors 17a-17c fitted to the supports 15a and 15b. Then the outputs of the photodetectors 17a-17c are shaped by a photodetecting circuit 19 and outputted to an external signal processing means, etc., so that the internal surface detection signal of a pipe P to be inspected and the position in the gravitational direction are made to correspond to each other.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to an inside pipe inspection device that optically detects the inner surface properties of pipes such as heat exchangers and other various types of piping.

[Prior Art] Various conventional devices for inspecting the inner surface of small-diameter pipes have been proposed, but all of them employ structures that use ultrasonic waves or light, and examples thereof are shown in FIGS. It is as shown in the figure. FIG. 3 is a schematic cross-sectional view of a conventional pipe inner surface inspection device using ultrasound, which includes an ultrasound probe (42) equipped with ultrasound transmission and reception functions and an ultrasound probe (42) disposed opposite to the ultrasound probe (42). A detection head (41) equipped with a reflecting member 43 is inserted into the brass pipe P to be tested, water is injected as an ultrasonic transmission medium into the brass pipe P to be tested, and the reflecting member (43) is aligned with its axis. Turn the ultrasonic probe (4
2), the ultrasonic wave is refracted at a right angle by the reflecting member (43), and is made incident on the inner peripheral surface of the tube to be inspected P, so that the reflected echo from the inner and outer surfaces of the tube to be inspected P is Sonic probe (
42) to detect the inner and outer diameters of the tube P to be inspected, irregularities on the surface, etc.

FIG. 4 is a schematic cross-sectional view showing a conventional optical tube inner surface inspection device.
2) At the tip of the operating shaft (54) is a detection head (51) in which the light receiving parts (53) are arranged in an inclined state so that their optical axes intersect with each other on the inner circumferential surface of the tube P to be inspected. It is configured to be fixed, and the detection head (51) is connected to the operation shaft (54).
is rotated and moved within the test cannula P to optically inspect the inner circumferential surface.

[Problems to be Solved by the Invention] Since the conventional pipe inspection device is configured as described above, it is unclear which part of the inner surface of the pipe P to be inspected in the circumferential direction, and it is difficult to detect defective parts. The disadvantage was that it was not possible to specify the location of

The present invention has been made to solve the above-mentioned problems, and it is an object of the present invention to provide a highly reliable pipe inspection device that can specify detection positions in the circumferential direction.

[Means for Solving the Problems] In the present invention, a rotation detection means for detecting rotation of the detection head is provided in the detection head.

[Operation] In the device according to the present invention, the rotation angle of the reference position of the detection head with respect to the direction of gravity is detected by the rotation detection means.

[Example] Hereinafter, an example of the present invention will be described with reference to the drawings. 1st
In the figure, (9) is a rotation detection unit fixed to a part of the detection head (51), and FIG. 2 is a configuration diagram showing details of the rotation detection means, (10) is a disk, and (11) is a circle. Board (10)
A weight attached to one place on the outer circumference of (12a), (
12b) and (12c) are tracks provided on the disc (1o), (13) is a shaft that is the rotation center of the disc (1o), and (14a) and (14b) are the shafts (13).
(15a), (15a), (
15b) is a support that supports the disk (10), (16
a), (16b), (L6c) are projectors disposed facing each of the plurality of tracks (12a), (12b), (12c), (17a), (17b),
(17c) is the receiver facing the emitter, (18)
(19) is the light receiver (17a),
A light receiving circuit is shown which receives the output signals from (17b) and (17c) and outputs them to the outside of the detection head (51).

In the apparatus according to the present invention, the inspection of the inner circumferential surface of the pipe P to be inspected is exactly the same as that described in the explanation of the operation of the conventional apparatus, but at the same time, the amount of rotation of the detection head (51) is detected. . That is, the rotation detection section (9) fixed within the detection head (51) executes this operation. An example of operation will be explained with reference to FIG. In the same figure, the disk (10) is the shaft (13)
and supports (15a) and (15b), but rotates freely by bearings (14a) and (14b). However, a weight (11
) is attached, and the other parts of the disk (10) are uniform, so the weight (11) is always stable in the direction of gravity. - force supports (15a), (15
b) is fixed to the detection head (51), so it rotates as the detection head (51) rotates, and the disk (10)
The positional relationship with the This change occurs in multiple tracks (12a), (12b), (12c) of the disc (10).
The optical marks (a) and (b) attached to the support (15
a), (15b) Floodlight (16
a), (16b), (16c), light receiver (17a)
, (17b), (17c). That is, each track (12a), (12
b), (12c) and the projector (16a), (
16b), (16c) Light beams are projected from the receivers (17a), (17b), (17c) placed facing each other.
This beam is received by the track (12a), (1
2b), (12c) Light does not pass through the optical mark (a) above, but passes through the optical mark (b), and tracks (12a), (12b), (12
c) is a circle concentric with the rotation center of the disk (10), and optical marks (a), (
Since the interval of (b) is configured to increase by two times,
From the output of the light receiver, the rotational state of the detection head (51) can be determined with a resolution of 2 to the N power based on the number N of tracks. The outputs of the photoreceptors (17a), (17b), and (17c) are shaped by the photoreceptor circuit (19) and output to an external signal processing means (not shown), which outputs the inner surface detection signal of the tube P to be inspected and the direction of gravity. The position will be associated with the .

In addition, in the above embodiment, a method of optically detecting the position of the disc (10) was shown, but this is also possible using a magnetic method using a combination of a magnetic mark and a magnetic sensor, or a method using uneven marks on the disc (10). It may be read by a change in capacitance or by an eddy current method, or the N rotation detection signals may be converted from parallel to serial and output via a single signal line.

[Effects of the Invention] As described above, according to the present invention, since the detection head rotation detecting means is provided in the detection head, it is possible to identify the location where the inner surface detection signal of the tube to be inspected is generated, and to detect the inside of the tube with high precision. An inspection device is obtained.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing the configuration of an apparatus according to an embodiment of the present invention, FIG. 2 is a schematic diagram for explaining the rotation detection means of the same apparatus, and FIGS. 3 and 4 are for explaining a conventional apparatus. FIG. In the figure, (3) is the wheel, (9) is the rotation detection unit, and (1
0) is a disk, (11) is a weight, (16) is a floodlight, (1
7) is a light receiver, (51) is a detection head, (52) is a light emitter, (53) is a light receiver, and (P) is a tube to be inspected. In addition, in the figures, the same reference numerals indicate the same or equivalent parts.

Claims (2)

[Claims] (1) In a device that detects the inner surface shape of the tube to be inspected by inserting a detection head movable in the axial direction into the tube to be inspected, the detection head includes a detection means for detecting the inner surface condition of the tube to be inspected; An in-pipe inspection device comprising: rotation detection means for detecting a rotational position of the detection head with respect to the direction of gravity. (2) The rotation detection means is comprised of a freely rotatable disk, a weight provided on the disk, and a detection means for reading the rotational position of the disk. pipe inspection equipment.